Buildbot requires a connection to a database to maintain certain state information, such as tracking pending build requests.
In the default configuration Buildbot uses a file-based SQLite database, stored in the state.sqlite file of the master's base directory.
Override this configuration with the db_url parameter.

Buildbot accepts a database configuration in a dictionary named db.
All keys are optional:

The max_idle argument for MySQL connections is unique to Buildbot, and should be set to something less than the wait_timeout configured for your server.
This controls the SQLAlchemy pool_recycle parameter, which defaults to no timeout.
Setting this parameter ensures that connections are closed and re-opened after the configured amount of idle time.
If you see errors such as _mysql_exceptions.OperationalError:(2006,'MySQLserverhasgoneaway'), this means your max_idle setting is probably too high.
showglobalvariableslike'wait_timeout'; will show what the currently configured wait_timeout is on your MySQL server.

Buildbot requires use_unique=True and charset=utf8, and will add them automatically, so they do not need to be specified in db_url.

MySQL defaults to the MyISAM storage engine, but this can be overridden with the storage_engine URL argument.

Buildbot uses a message-queueing system to handle communication within the master.
Messages are used to indicate events within the master, and components that are interested in those events arrange to receive them.

The message queueing implementation is configured as a dictionary in the mq option.
The type key describes the type of MQ implemetation to be used.
Note that the implementation type cannot be changed in a reconfig.

The available implemenetation types are described in the following sections.

This is the default MQ implementation.
Similar to SQLite, it has no additional software dependencies, but does not support multi-master mode.

Note that this implementation also does not support message persistence across a restart of the master.
For example, if a change is received, but the master shuts down before the schedulers can create build requests for it, then those schedulers will not be notified of the change when the master starts again.

The debug key, which defaults to False, can be used to enable logging of every message produced on this master.

At the moment, wamp is the only message queue implementation for multimaster.
It has been privileged as this is the only message queue that have very solid support for Twisted.
Other more common message queue systems like RabbitMQ (using the AMQP protocol) do not have convincing driver for twisted, and this would require to run on threads, which will add an important performance overhead.

This is a MQ implementation using wamp protocol.
This implementation uses Python Autobahn wamp client library, and is fully asynchronous (no use of threads).
To use this implementation, you need a wamp router like Crossbar.

Please refer to Crossbar documentation for more details, but the default Crossbar setup will just work with Buildbot, provided you use the example mq configuration above, and start Crossbar with:

# of course, you should work in a virtualenv...
pip install crossbar
crossbar init
crossbar start

The implementation does not yet support wamp authentication.
This MQ allows buildbot to run in multi-master mode.

Note that this implementation also does not support message persistence across a restart of the master.
For example, if a change is received, but the master shuts down before the schedulers can create build requests for it, then those schedulers will not be notified of the change when the master starts again.

router_url (mandatory): points to your router websocket url.

Buildbot is only supporting wamp over websocket, which is a sub-protocol of http.
SSL is supported using wss:// instead of ws://.

realm (optional, defaults to buildbot): defines the wamp realm to use for your buildbot messages.

See Multimaster for details on the Multi-master mode in Buildbot Nine.

By default, Buildbot makes coherency checks that prevents typo in your master.cfg
It make sure schedulers are not referencing unknown builders, and enforces there is at least one builder.

In the case of a asymmetric multimaster, those coherency checks can be harmful and prevent you to implement what you want.
For example you might want to have one master dedicated to the UI, so that a big load generated by builds will not impact page load times.

To enable multi-master mode in this configuration, you will need to set the multiMaster option so that buildbot doesn't warn about missing schedulers or builders.

title is a short string that will appear at the top of this buildbot installation's home page (linked to the titleURL).

titleURL is a URL string that must end with a slash (/).
HTML status displays will show title as a link to titleURL.
This URL is often used to provide a link from buildbot HTML pages to your project's home page.

The buildbotURL string should point to the location where the buildbot's internal web server is visible.
This URL must end with a slash (/).

When status notices are sent to users (e.g., by email or over IRC), buildbotURL will be used to create a URL to the specific build or problem that they are being notified about.

The logCompressionLimit enables compression of build logs on disk for logs that are bigger than the given size, or disables that completely if set to False.
The default value is 4096, which should be a reasonable default on most file systems.
This setting has no impact on status plugins, and merely affects the required disk space on the master for build logs.

The logCompressionMethod controls what type of compression is used for build logs.
The default is 'gz', and the other valid option are 'raw' (no compression), 'gz' or 'lz4' (required lz4 package).

The logMaxSize parameter sets an upper limit (in bytes) to how large logs from an individual build step can be.
The default value is None, meaning no upper limit to the log size.
Any output exceeding logMaxSize will be truncated, and a message to this effect will be added to the log's HEADER channel.

If logMaxSize is set, and the output from a step exceeds the maximum, the logMaxTailSize parameter controls how much of the end of the build log will be kept.
The effect of setting this parameter is that the log will contain the first logMaxSize bytes and the last logMaxTailSize bytes of output.
Don't set this value too high, as the the tail of the log is kept in memory.

The logEncoding parameter specifies the character encoding to use to decode bytestrings provided as logs.
It defaults to utf-8, which should work in most cases, but can be overridden if necessary.
In extreme cases, a callable can be specified for this parameter.
It will be called with byte strings, and should return the corresponding Unicode string.

This setting can be overridden for a single build step with the logEncoding step parameter.
It can also be overridden for a single log file by passing the logEncoding parameter to addLog.

Buildbot stores historical information in its database.
In a large installation, these can quickly consume disk space, yet in many cases developers never consult this historical information.

The changeHorizon key determines how many changes the master will keep a record of.
One place these changes are displayed is on the waterfall page.
This parameter defaults to 0, which means keep all changes indefinitely.

The buildHorizon specifies the minimum number of builds for each builder which should be kept.
The logHorizon gives the minimum number of builds for which logs should be maintained; this parameter must be less than or equal to buildHorizon.
Builds older than logHorizon but not older than buildHorizon will maintain their overall status and the status of each step, but the logfiles will be deleted.

The caches configuration key contains the configuration for Buildbot's in-memory caches.
These caches keep frequently-used objects in memory to avoid unnecessary trips to the database.
Caches are divided by object type, and each has a configurable maximum size.

The default size for each cache is 1, except where noted below.
A value of 1 allows Buildbot to make a number of optimizations without consuming much memory.
Larger, busier installations will likely want to increase these values.

The available caches are:

Changes

the number of change objects to cache in memory.
This should be larger than the number of changes that typically arrive in the span of a few minutes, otherwise your schedulers will be reloading changes from the database every time they run.
For distributed version control systems, like Git or Hg, several thousand changes may arrive at once, so setting this parameter to something like 10000 isn't unreasonable.

This parameter is the same as the deprecated global parameter changeCacheSize.
Its default value is 10.

Builds

The buildCacheSize parameter gives the number of builds for each builder which are cached in memory.
This number should be larger than the number of builds required for commonly-used status displays (the waterfall or grid views), so that those displays do not miss the cache on a refresh.

This parameter is the same as the deprecated global parameter buildCacheSize.
Its default value is 15.

chdicts

The number of rows from the changes table to cache in memory.
This value should be similar to the value for Changes.

BuildRequests

The number of BuildRequest objects kept in memory.
This number should be higher than the typical number of outstanding build requests.
If the master ordinarily finds jobs for BuildRequests immediately, you may set a lower value.

SourceStamps

the number of SourceStamp objects kept in memory.
This number should generally be similar to the number BuildRequesets.

ssdicts

The number of rows from the sourcestamps table to cache in memory.
This value should be similar to the value for SourceStamps.

objectids

The number of object IDs - a means to correlate an object in the Buildbot configuration with an identity in the database--to cache.
In this version, object IDs are not looked up often during runtime, so a relatively low value such as 10 is fine.

usdicts

The number of rows from the users table to cache in memory.
Note that for a given user there will be a row for each attribute that user has.

By default, buildbot will attempt to start builds on builders in order, beginning with the builder with the oldest pending request.
Customize this behavior with the prioritizeBuilders configuration key, which takes a callable.
See Builder Priority Functions for details on this callable.

This parameter controls the order that the build master can start builds, and is useful in situations where there is resource contention between builders, e.g., for a test database.
It does not affect the order in which a builder processes the build requests in its queue.
For that purpose, see Prioritizing Builds.

The buildmaster will listen on a TCP port of your choosing for connections from workers.
It can also use this port for connections from remote Change Sources, status clients, and debug tools.
This port should be visible to the outside world, and you'll need to tell your worker admins about your choice.

It does not matter which port you pick, as long it is externally visible; however, you should probably use something larger than 1024, since most operating systems don't allow non-root processes to bind to low-numbered ports.
If your buildmaster is behind a firewall or a NAT box of some sort, you may have to configure your firewall to permit inbound connections to this port.

c['protocols']['pb']['port'] is a strports specification string, defined in the twisted.application.strports module (try pydoctwisted.application.strports to get documentation on the format).

This means that you can have the buildmaster listen on a localhost-only port by doing:

c['protocols']={"pb":{"port":"tcp:10000:interface=127.0.0.1"}}

This might be useful if you only run workers on the same machine, and they are all configured to contact the buildmaster at localhost:10000.

Note

In Buildbot versions <=0.8.8 you might see slavePortnum option.
This option contains same value as c['protocols']['pb']['port'] but not recomended to use.

If you set manhole to an instance of one of the classes in buildbot.manhole, you can telnet or ssh into the buildmaster and get an interactive Python shell, which may be useful for debugging buildbot internals.
It is probably only useful for buildbot developers.
It exposes full access to the buildmaster's account (including the ability to modify and delete files), so it should not be enabled with a weak or easily guessable password.

There are three separate Manhole classes.
Two of them use SSH, one uses unencrypted telnet.
Two of them use a username+password combination to grant access, one of them uses an SSH-style authorized_keys file which contains a list of ssh public keys.

Note

Using any Manhole requires that pycrypto and pyasn1 be installed.
These are not part of the normal Buildbot dependencies.

manhole.AuthorizedKeysManhole

You construct this with the name of a file that contains one SSH public key per line, just like ~/.ssh/authorized_keys.
If you provide a non-absolute filename, it will be interpreted relative to the buildmaster's base directory.

manhole.PasswordManhole

This one accepts SSH connections but asks for a username and password when authenticating.
It accepts only one such pair.

manhole.TelnetManhole

This accepts regular unencrypted telnet connections, and asks for a username/password pair before providing access.
Because this username/password is transmitted in the clear, and because Manhole access to the buildmaster is equivalent to granting full shell privileges to both the buildmaster and all the workers (and to all accounts which then run code produced by the workers), it is highly recommended that you use one of the SSH manholes instead.

# some examples:frombuildbot.pluginsimportutilc['manhole']=util.AuthorizedKeysManhole(1234,"authorized_keys")c['manhole']=util.PasswordManhole(1234,"alice","mysecretpassword")c['manhole']=util.TelnetManhole(1234,"bob","snoop_my_password_please")

The Manhole instance can be configured to listen on a specific port.
You may wish to have this listening port bind to the loopback interface (sometimes known as lo0, localhost, or 127.0.0.1) to restrict access to clients which are running on the same host.

To have the Manhole listen on all interfaces, use "tcp:9999" or simply 9999.
This port specification uses twisted.application.strports, so you can make it listen on SSL or even UNIX-domain sockets if you want.

Note that using any Manhole requires that the TwistedConch package be installed.

The buildmaster's SSH server will use a different host key than the normal sshd running on a typical unix host.
This will cause the ssh client to complain about a host key mismatch, because it does not realize there are two separate servers running on the same host.
To avoid this, use a clause like the following in your .ssh/config file:

Host remotehost-buildbot
HostName remotehost
HostKeyAlias remotehost-buildbot
Port 9999
# use 'user' if you use PasswordManhole and your name is not 'admin'.
# if you use AuthorizedKeysManhole, this probably doesn't matter.
User admin

After you have connected to a manhole instance, you will find yourself at a Python prompt.
You have access to two objects: master (the BuildMaster) and status (the master's Status object).
Most interesting objects on the master can be reached from these two objects.

To aid in navigation, the show method is defined.
It displays the non-method attributes of an object.

metrics can be a dictionary that configures various aspects of the metrics subsystem.
If metrics is None, then metrics collection, logging and reporting will be disabled.

log_interval determines how often metrics should be logged to twistd.log.
It defaults to 60s.
If set to 0 or None, then logging of metrics will be disabled.
This value can be changed via a reconfig.

periodic_interval determines how often various non-event based metrics are collected, such as memory usage, uncollectable garbage, reactor delay.
This defaults to 10s.
If set to 0 or None, then periodic collection of this data is disabled.
This value can also be changed via a reconfig.

Read more about metrics in the Metrics section in the developer documentation.

The Statistics Service (stats service for short) supports for collecting arbitrary data from within a running Buildbot instance and export it do a number of storage backends.
Currently, only InfluxDB is supported as a storage backend.
Also, InfluxDB (or any other storage backend) is not a mandatory dependency.
Buildbot can run without it although StatsService will be of no use in such a case.
At present, StatsService can keep track of build properties, build times (start, end, duration) and arbitrary data produced inside Buildbot (more on this later).

This is the main class for statistics service.
It is initialized in the master configuration as show in the example above.
It takes two arguments:

storage_backends

A list of storage backends (see Storage Backends).
In the example above, stats.InfluxStorageService is an instance of a storage backend.
Each storage backend is an instances of subclasses of statsStorageBase.

Instance of this class declares which properties must be captured and sent to the Storage Backends.
It takes the following arguments:

builder_name

The name of builder in which the property is recorded.

property_name

The name of property needed to be recorded as a statistic.

callback=None

(Optional) A custom callback function for this class.
This callback function should take in two arguments - build_properties (dict) and property_name (str) and return a string that will be sent for storage in the storage backends.

regex=False

If this is set to True, then the property name can be a regular expression.
All properties matching this regular expression will be sent for storage.

class buildbot.statistics.capture.CapturePropertyAllBuilders

Instance of this class declares which properties must be captured on all builders and sent to the Storage Backends.
It takes the following arguments:

property_name

The name of property needed to be recorded as a statistic.

callback=None

(Optional) A custom callback function for this class.
This callback function should take in two arguments - build_properties (dict) and property_name (str) and return a string that will be sent for storage in the storage backends.

regex=False

If this is set to True, then the property name can be a regular expression.
All properties matching this regular expression will be sent for storage.

class buildbot.statistics.capture.CaptureBuildStartTime

Instance of this class declares which builders' start times are to be captured and sent to Storage Backends.
It takes the following arguments:

builder_name

The name of builder whose times are to be recorded.

callback=None

(Optional) A custom callback function for this class.
This callback function should take in a Python datetime object and return a string that will be sent for storage in the storage backends.

class buildbot.statistics.capture.CaptureBuildStartTimeAllBuilders

Instance of this class declares start times of all builders to be captured and sent to Storage Backends.
It takes the following arguments:

callback=None

(Optional) A custom callback function for this class.
This callback function should take in a Python datetime object and return a string that will be sent for storage in the storage backends.

class buildbot.statistics.capture.CaptureBuildEndTime

Exactly like CaptureBuildStartTime except it declares the builders whose end time is to be recorded.
The arguments are same as CaptureBuildStartTime.

class buildbot.statistics.capture.CaptureBuildEndTimeAllBuilders

Exactly like CaptureBuildStartTimeAllBuilders except it declares all builders' end time to be recorded.
The arguments are same as CaptureBuildStartTimeAllBuilders.

class buildbot.statistics.capture.CaptureBuildDuration

Instance of this class declares the builders whose build durations are to be recorded.
It takes the following arguments:

builder_name

The name of builder whose times are to be recorded.

report_in='seconds'

Can be one of three: 'seconds', 'minutes', or 'hours'.
This is the units in which the build time will be reported.

callback=None

(Optional) A custom callback function for this class.
This callback function should take in two Python datetime objects - a start_time and an end_time and return a string that will be sent for storage in the storage backends.

class buildbot.statistics.capture.CaptureBuildDurationAllBuilders

Instance of this class declares build durations to be recorded for all builders.
It takes the following arguments:

report_in='seconds'

Can be one of three: 'seconds', 'minutes', or 'hours'.
This is the units in which the build time will be reported.

callback=None

(Optional) A custom callback function for this class.
This callback function should take in two Python datetime objects - a start_time and an end_time and return a string that will be sent for storage in the storage backends.

class buildbot.statistics.capture.CaptureData

Instance of this capture class is for capturing arbitrary data that is not stored as build-data.
Needs to be used in conjunction with yieldMetricsValue (See Using StatsService.yieldMetricsValue).
Takes the following arguments:

data_name

The name of data to be captured.
Same as in yieldMetricsValue.

builder_name

The name of builder whose times are to be recorded.

callback=None

The callback function for this class.
This callback receives the data sent to yieldMetricsValue as post_data (See Using StatsService.yieldMetricsValue).
It must return a string that is to be sent to the storage backends for storage.

class buildbot.statistics.capture.CaptureDataAllBuilders

Instance of this capture class for capturing arbitrary data that is not stored as build-data on all builders.
Needs to be used in conjunction with yieldMetricsValue (See Using StatsService.yieldMetricsValue).
Takes the following arguments:

data_name

The name of data to be captured.
Same as in yieldMetricsValue.

callback=None

The callback function for this class.
This callback receives the data sent to yieldMetricsValue as post_data (See Using StatsService.yieldMetricsValue).
It must return a string that is to be sent to the storage backends for storage.

Storage backends are responsible for storing any statistics data sent to them.
A storage backend will generally be some sort of a database-server running on a machine.
(Note: This machine may be different from the one running BuildMaster)

Since buildbot 0.9.0, buildbot has a simple feature which sends usage analysis info to buildbot.net.
This is very important for buildbot developers to understand how the community is using the tools.
This allows to better prioritize issues, and understand what plugins are actually being used.
This will also be a tool to decide whether to keep support for very old tools.
For example buildbot contains support for the venerable CVS, but we have no information whether it actually works beyond the unit tests.
We rely on the community to test and report issues with the old features.

With BuildbotNetUsageData, we can know exactly what combination of plugins are working together, how much people are customizing plugins, what versions of the main dependencies people run.

We take your privacy very seriously.

BuildbotNetUsageData will never send information specific to your Code or Intellectual Property.
No repository url, shell command values, host names, ip address or custom class names.
If it does, then this is a bug, please report.

We still need to track unique number for installation.
This is done via doing a sha1 hash of master's hostname, installation path and fqdn.
Using a secure hash means there is no way of knowing hostname, path and fqdn given the hash, but still there is a different hash for each master.

You can see exactly what is sent in the master's twisted.log.
Usage data is sent every time the master is started.

Plugins usages:
This counts the number of time each class of buildbot is used in your configuration.
This counts workers, builders, steps, schedulers, change sources.
If the plugin is subclassed, then it will be prefixed with a >

c['buildbotNetUsageData']=myCustomFunction. You can also specify exactly what to send using a callback.

The custom function will take the generated data from full report in the form of a dictionary, and return a customized report as a jsonable dictionary. You can use this to filter any information you don't want to disclose. You can use a custom http_proxy environment variable in order to not send any data while developing your callback.

user_managers contains a list of ways to manually manage User Objects within Buildbot (see User Objects).
Currently implemented is a commandline tool buildbot user, described at length in user.
In the future, a web client will also be able to manage User Objects and their attributes.

As shown above, to enable the buildbot user tool, you must initialize a CommandlineUserManager instance in your master.cfg.
CommandlineUserManager instances require the following arguments:

username

This is the username that will be registered on the PB connection and need to be used when calling buildbot user.

passwd

This is the passwd that will be registered on the PB connection and need to be used when calling buildbot user.

port

The PB connection port must be different than c['protocols']['pb']['port'] and be specified when calling buildbot user

This option configures the validation applied to user inputs of various types.
This validation is important since these values are often included in command-line arguments executed on workers.
Allowing arbitrary input from untrusted users may raise security concerns.

The keys describe the type of input validated; the values are compiled regular expressions against which the input will be matched.
The defaults for each type of input are those given in the example, above.

The revlink parameter is used to create links from revision IDs in the web status to a web-view of your source control system.
The parameter's value must be a callable.

By default, Buildbot is configured to generate revlinks for a number of open source hosting platforms.

The callable takes the revision id and repository argument, and should return an URL to the revision.
Note that the revision id may not always be in the form you expect, so code defensively.
In particular, a revision of "??" may be supplied when no other information is available.

Note that SourceStamps that are not created from version-control changes (e.g., those created by a Nightly or Periodic scheduler) may have an empty repository string, if the repository is not known to the scheduler.

Buildbot provides two helpers for generating revision links.
buildbot.revlinks.RevlinkMatcher takes a list of regular expressions, and replacement text.
The regular expressions should all have the same number of capture groups.
The replacement text should have sed-style references to that capture groups (i.e. '1' for the first capture group), and a single '%s' reference, for the revision ID.
The repository given is tried against each regular expression in turn.
The results are the substituted into the replacement text, along with the revision ID to obtain the revision link.

For any incoming change, the codebase is set to ''.
This codebase value is sufficient if all changes come from the same repository (or clones).
If changes come from different repositories, extra processing will be needed to determine the codebase for the incoming change.
This codebase will then be a logical name for the combination of repository and or branch etc.

The codebaseGenerator accepts a change dictionary as produced by the buildbot.db.changes.ChangesConnectorComponent, with a changeid equal to None.